永磁同步电动机新型滑模观测器无传感器控制

Sensorless Control Using a Novel Sliding Mode Observer for PMSM Speed Control System

根据滑模变结构控制理论以及永磁同步电动机的数学模型,在传统滑模观测器的基础上,设计了一种将反电势估算值反馈引入到定子电流观测计算中的新型滑模观测器,利用该观测器对永磁同步电动机的转子位置和转速进行了实时在线估算。针对采用滑模控制导致系统出现的抖振现象以及加上其他干扰引起转速计算精度不高的问题,采用了将传统的开关函数更换为近似饱和函数以及锁相环代替直接微分计算转速的方法,有效地抑制了抖振问题,提高了估算精度。仿真实验验证了该新型滑模观测器的正确性和有效性。

Based on the sliding mode variable structure control theory and the mathematical model of permanent magnet synchronous motor（PMSM）, a sliding mode observer introducing back EMF estimation value into stator current observer was designed. The rotor position and speed of PMSM were estimated online using this observer. Methods of using the ap- proximate saturation function instead of the traditional switch function, the phase locked loop instead of the direct differenti- al calculation were adopted to suppress buffeting problem and improve the estimation accuracy. The simulation results prove that the slidin~ mode observer is correct and effective.